Bottleneck Theory Research Articles

Design Rules, Volume 2: How Technology Shapes Organizations: Chapter 17 The Wintel Standards-based Platform

The purpose of this chapter is to use the theory of bottlenecks laid out in the previous chapter to better understand the dynamics of an open standards-based platform. I describe how the Wintel platform evolved from 1990 through 2000 under joint sponsorship of Intel and Microsoft. I first describe a series of technical bottlenecks that arose in the early 1990s concerning the “bus architecture” of IBM-compatible PCs. Intel’s management of buses demonstrates how, under conditions of distributed modular complementarity (DMC), a platform sponsor can reconfigure the modular structure of a technical system and property rights within the system to increase system-wide throughput, while protecting its own strategic bottleneck from disintermediation. I go on to describe how Microsoft used platform envelopment to establish a second strategic bottleneck in productivity software and later to respond to the threat of disintermediation from platform-independent Internet browsers. I end the chapter by discussing the conditions under which shared platform sponsorship can be a long-term dynamic equilbrium.

Design Rules, Volume 2: How Technology Shapes Organizations: Chapter 16 Capturing Value by Controlling Bottlenecks in Open Platform Systems

The purpose of this chapter is to investigate the means by which firms capture value in open platform systems. It combines the theory of a platform as a provider of options with the theory of bottlenecks developed in Chapters 7, 8 and 9. I argue that, in an open platform system, firms capture value by: (1) controlling one or more strategic bottlenecks; (2) finding and fixing flow bottlenecks at the core of the system; (3) introducing accelerators and/or subsidiary platorms; and (4) avoiding disintermediation of the parts of the platform they control. I begin by arguing that the surplus value created by complementarities within a technical system will be split among the owners of the unique and essential components—the strategic bottlenecks in the system. However, most platforms must also execute a series of steps which are subject to “flow production” bottlenecks. Finding and fixing these technical bottlenecks is another way to capture value. In addition, two types of platform improvements provide further opportunities for value capture. “Accelerators” speed up the processing of options, while “subsidiary” platforms increase the range of options available to users. Finally, members of a platform system or new entrants may seek to supplant the owner of a strategic bottleneck by “disintermediating” platform components. I describe four generic methods of disintermediation: substitution; reverse engineering; platform independent complements; and platform envelopment.

Multiple ‘Genetic Bottleneck Theory’ of Humans and the House Mouse via Chilling Enzyme ∆12-Desaturase

The super Toba volcano eruption in Indonesia around 70,000-75,000 years ago might have reduced the human’s world population to around 10,000 individuals. Such a dramatic scenario is indicated by the term 'genetic bottleneck theory' because the whole human species was on a global scale of nearly extinct. Here we show for modern humans and the common house mouse (strain C57bl6) they both possess a ‘chilling’ enzyme ∆12-desaturase in order to avoid that the body core temperature drops below 35.0 °C (95.0 °F). We postulate the hypothesis that the survivors of the Toba volcano eruption had been selected on their ability to maintain a relatively constant brain- and body core temperature in the face of a notoriously inconstant environmental temperature characterized by extreme adverse cold environmental conditions due to a following ‘Toba glacial winter’. Surviving organisms originating from this event must have been in possession of the chilling enzyme ∆12- desaturase.

Road traffic bottleneck analysis for expressway for safety under disaster events using blockchain machine learning

To analyze the largest capacity of expressway network, the concept of road network bottleneck and its analyzing method are presented. Based on the bottleneck theory in Graphics, road network bottleneck is defined, and Ford-Fulkerson method and super origin-destination, short for OD, method are adopted for analysis of single OD and multiple OD road networks respectively. With Beijing-Hongkong-Macau expressway in Anyang-Xinxiang road network, Henan province, as a case study, application of road network bottleneck was investigated in aspects of network entrance management, network congestion points analysis and traffic assignment. For overall analysis of the congestion points in road network, the concept of bottlenecks chain corridor was presented. Bottlenecks chain corridors are key corridors for traffic diversion under disastrous events, which have major impact on the operation of road network. The case study indicates that road network bottleneck and bottlenecks chain corridor have significant value in expressway network operation management.

A simulation framework for modeling urban freight operations impacts on traffic networks

This paper presents a traffic simulation framework to reproduce urban freight movements, particularly concerning double-parked delivery operations. Since freight movements affect traffic and vice versa, we propose a hybrid framework that simulates traffic phenomena macroscopically and, at the same time, allows tracking delivery vehicles along their routes throughout the entire simulation. The traffic simulation framework is based on the Lighthill–Whitham–Richards macroscopic model as well as the theory of bottlenecks. The traffic component of the model can be coupled with a generic parking model. Since a novel faster version of the Lax-Hopf Formula is used in the traffic simulation, the proposed framework can perform efficient simulations. Because of this hybrid nature, the framework is suitable for simulations of large scenarios and for evaluations of City Logistic measures to tackle the last-mile problem. We show this in the second part of the study with two different measures: shifting delivery operations to off-peak hours, and prohibiting deliveries on critical streets. While the benefits deriving from the first strategy are evident, the effects of the second one are less clear because of the complexity of network interactions.

Understanding the Cognition Related to Mathematics Difficulties: A Meta-Analysis on the Cognitive Deficit Profiles and the Bottleneck Theory

The current study investigated the cognitive deficit profiles among individuals with mathematics difficulties (MD) and potential moderators and mechanism for these profiles. Seventy-five cognitive profiling studies on MD were included, representing a total of 13,001 individuals and 126 independent samples. Results showed that compared with typically developing individuals, individuals with MD showed deficits (from most severe to less severe) in phonological processing, processing speed, working memory, attention, short-term memory, executive functions, and visuospatial skills. Moderation analyses indicated that comorbidity (with reading disabilities) and types of MD screening affected the cognitive deficits. Severity of MD was related to processing speed deficits. Deficits in phonological processing and attention were more severe in younger individuals with MD. Deficits in processing speed and working memory were most severe in the numerical domain. Deficits in low-level cognitive skills (i.e., processing speed and short-term memory) could not completely explain the deficits in high-level skills (i.e., working memory, attention, and executive functions), partially supporting the bottleneck theory. These findings, taken together, suggest that (a) deficits in processing speed and working memory are most salient and stable cognitive markers of MD, (b) numerical-processing deficit and the cognitive deficits of MD are relatively independent from each other, and (c) MD may be a discrete construct with heterogeneity reflected by MD subtypes and age. Implications for incorporating cognition in the diagnosis and the interventions for MD are discussed.

Evaluation of average travel delay caused by moving bottlenecks on highways.

This paper presents a modelling framework to evaluate travel delay of all vehicles influenced by moving bottlenecks on highways. During the derivation of analytical formulas, the arrival of slow vehicles was approximated by a Poisson process based on the assumption that they occupied a constant low proportion of the traffic stream. The mathematical analysis process was developed from moving bottlenecks with the same velocity to those with multiple different velocities, and the closed-form expression of expected average travel delay was obtained by utilizing kinematic-wave moving bottleneck theory, gap acceptance theory, probability theory and renewal theory. Model validation and parameters sensitive analysis were conducted by simulation relying on the open source database of US highway 10. The maximum passing rate and the macroscopic parameters of initial traffic state with maximum delay could be found by means of approximate formulas. The proposed modeling framework can be applied for evaluating impacts of slow vehicles on highway operation quantifiably, based on which traffic managements like truck prohibited period decision and speed or lane restriction could be made more scientifically.

Categorization of Breast Cancer Cell with the Help of Information Bottleneck Theory

Categorization of Breast Cancer Cell with the Help of Information Bottleneck Theory

A fuzzy co-clustering algorithm for biomedical data.

Fuzzy co-clustering extends co-clustering by assigning membership functions to both the objects and the features, and is helpful to improve clustering accurarcy of biomedical data. In this paper, we introduce a new fuzzy co-clustering algorithm based on information bottleneck named ibFCC. The ibFCC formulates an objective function which includes a distance function that employs information bottleneck theory to measure the distance between feature data point and the feature cluster centroid. Many experiments were conducted on five biomedical datasets, and the ibFCC was compared with such prominent fuzzy (co-)clustering algorithms as FCM, FCCM, RFCC and FCCI. Experimental results showed that ibFCC could yield high quality clusters and was better than all these methods in terms of accuracy.

Bottleneck breakthrough, action learning and transformation capability

Purpose – The purpose of this paper is to demonstrate the main advantages of integrating bottleneck theory, action learning and transformation capabilities to phenomenon and process analysis systems. Design/methodology/approach – This paper selects three typical cases, using grounded theory standardized coding procedures, and selects exploratory case study approach. Findings – Inward small and medium manufacturing enterprises use the bottleneck breakthrough program and provide a correct knowledge input for action learning. Action learning provides a strong guarantee that for the implementation of bottleneck breakthrough program, programming and action learning are required to continually solve problems and achieve goals in the process. Research limitations/implications – The authors used inward manufacturing small- and medium-sized enterprises as research subjects The authors did not analysis the role of knowledge services; the future studies could explore how to improve the performance through the transformation value co-creation. Practical implications – Because of the lack of resources and capacity, small- and medium-sized enterprise adopt appropriate micro-innovation and continuous micro-transformation to break the bottleneck stage and achieve small victories. Originality/value – Learning and development enterprises are not only through multinational clients which restructuring enhance the learning capacity of the international M & A path. It does not conduct thorough and comprehensive change, and also not related to the structural of readjustment organization. In fact, the radical change and transformation strategy is different than other strategies.

Error-related processing in adult males with elevated psychopathic traits.

Psychopathy is a serious personality disorder characterized by dysfunctional affective and behavioral symptoms. In incarcerated populations, elevated psychopathic traits have been linked to increased rates of violent recidivism. Cognitive processes related to error processing have been shown to differentiate individuals with high and low psychopathic traits and may contribute to poor decision making that increases the risk of recidivism. Error processing abnormalities related to psychopathy may be attributable to error-monitoring (error detection) or posterror processing (error evaluation). A recent 'bottleneck' theory predicts deficiencies in posterror processing in individuals with high psychopathic traits. In the current study, incarcerated males (n = 93) performed a Go/NoGo response inhibition task while event-related potentials (ERPs) were recorded. Classic time-domain windowed component and principal component analyses were used to measure error-monitoring (as measured with the error-related negativity [ERN/Ne]) and posterror processing (as measured with the error positivity [Pe]). Psychopathic traits were assessed using Hare's Psychopathy Checklist-Revised (PCL-R). PCL-R Total score, Factor 1 (interpersonal-affective traits), and Facet 3 (lifestyle traits) scores were positively related to posterror processes (i.e., increased Pe amplitude) but unrelated to error-monitoring processes (i.e., ERN/Ne). These results support the attentional bottleneck theory and further describe deficiencies related to elevated psychopathic traits that could be beneficial for new treatment strategies for psychopathy.

On the importance of Task 1 and error performance measures in PRP dual-task studies.

The psychological refractory period (PRP) paradigm is a dominant research tool in the literature on dual-task performance. In this paradigm a first and second component task (i.e., Task 1 and Task 2) are presented with variable stimulus onset asynchronies (SOAs) and priority to perform Task 1. The main indicator of dual-task impairment in PRP situations is an increasing Task 2-RT with decreasing SOAs. This impairment is typically explained with some task components being processed strictly sequentially in the context of the prominent central bottleneck theory. This assumption could implicitly suggest that processes of Task 1 are unaffected by Task 2 and bottleneck processing, i.e., decreasing SOAs do not increase reaction times (RTs) and error rates of the first task. The aim of the present review is to assess whether PRP dual-task studies included both RT and error data presentations and statistical analyses and whether studies including both data types (i.e., RTs and error rates) show data consistent with this assumption (i.e., decreasing SOAs and unaffected RTs and/or error rates in Task 1). This review demonstrates that, in contrast to RT presentations and analyses, error data is underrepresented in a substantial number of studies. Furthermore, a substantial number of studies with RT and error data showed a statistically significant impairment of Task 1 performance with decreasing SOA. Thus, these studies produced data that is not primarily consistent with the strong assumption that processes of Task 1 are unaffected by Task 2 and bottleneck processing in the context of PRP dual-task situations; this calls for a more careful report and analysis of Task 1 performance in PRP studies and for a more careful consideration of theories proposing additions to the bottleneck assumption, which are sufficiently general to explain Task 1 and Task 2 effects.

A parallel clustering method combined information bottleneck theory and centroid-based clustering

Clustering is an important research topic of data mining. Information bottleneck theory-based clustering method is suitable for dealing with complicated clustering problems because that its information loss metric can measure arbitrary statistical relationships between samples. It has been widely applied to many kinds of areas. With the development of information technology, the electronic data scale becomes larger and larger. Classical information bottleneck theory-based clustering method is out of work to deal with large-scale dataset because of expensive computational cost. Parallel clustering method based on MapReduce model is the most efficient method to deal with large-scale data-intensive clustering problems. A parallel clustering method based on MapReduce model is developed in this paper. In the method, parallel information bottleneck theory clustering method based on MapReduce is proposed to determine the initial clustering center. An objective method is proposed to determine the final number of clusters automatically. Parallel centroid-based clustering method is proposed to determine the final clustering result. The clustering results are visualized with interpolation MDS dimension reduction method. The efficiency of the method is illustrated with a practical DNA clustering example.

Stochastic bottleneck capacity, merging traffic and morning commute

This paper investigates the impact of stochastic capacity at the downstream bottleneck after a merge and the impact of merging behavior on the morning commuters’ departure-time patterns. The classic bottleneck theory is extended to include a uniformly distributed capacity and the commuters’ equilibrium departure patterns are derived for two different merging rules. The results show that uncertainty in the bottleneck capacity increases the commuters’ mean trip cost and lengthens the peak period, and that the system total cost is lower under give-way merging than under a fixed-rate merging. Capacity paradoxes with dynamic user responses are found under both merging rules.

May We Have Your Attention Please? Human-Rights NGOs and the Problem of Global Communication

Historically, nongovernmental organizations (NGOs) have relied on mainstream news media to expose human-rights violations and encourage governments to pressure the perpetrators. Thanks to the Internet, NGOs are crafting new strategies for conducting information politics. Despite the obvious democratization of access to the means of communication, however, the new media may in fact represent a more challenging environment in which to be heard for some groups seeking global attention. We draw on agenda-setting research to develop a theory of global attention bottlenecks and use it to explain the success of 257 transnational human-rights groups at generating attention in both international mainstream news media and social media outlets. We conclude that most NGOs lack the organizational resources to compete effectively for either traditional news coverage or for public attention and that the Internet is unlikely to resolve the problem of global communication.

Analytical Derivation of Capacity at Diverging Junctions

Freeway congestion occurs mainly at discontinuities of the road network, such as merges, weaving sections, and diverges. Reliable tools are needed for estimating the operations at these discontinuities and evaluating their capacity. This paper proposes an analytical model that estimates the capacity at a diverging junction according to the kinematic wave theory of Lighthill, Whitham, and Richards. The model assumes that exiting vehicles drive temporarily at a speed that is lower than the free-flow speed. The slow vehicles are considered moving bottlenecks. In the methodology, the acceleration is assumed to be infinite in a first step. But, because it is a key factor in explaining the capacity drop, this assumption is relaxed in a second step through a constant acceleration rate used for all the vehicles. In this study, the moving bottleneck theory is used to compute the effective flow passing the diverging junction and the corresponding relative capacity drop. The analytical results are assessed with microsimulation results.

Lack of Structural Variation but Extensive Length Polymorphisms and Heteroplasmic Length Variations in the Mitochondrial DNA Control Region of Highly Inbred Crested Ibis, Nipponia nippon

The animal mitochondrial DNA (mtDNA) length polymorphism and heteroplasmy are accepted to be universal. Here we report the lack of structural variation but the presence of length polymorphism as well as heteroplasmy in mtDNA control region of an endangered avian species – the Crested Ibis (Nipponia nippon). The complete control region was directly sequenced while the distribution pattern and inheritance of the length variations were examined using both direct sequencing and genotyping of the PCR fragments from captive birds with pedigrees, wild birds and a historical specimen. Our results demonstrated that there was no structural variation in the control region, however, different numbers of short tandem repeats with an identical motif of CA3CA2CA3 at the 3′-end of the control region determined the length polymorphisms among and heteroplasmy within individual birds. There were one to three predominant fragments in every bird; nevertheless multiple minor fragments coexist in all birds. These extremely high polymorphisms were suggested to have derived from the ‘replication slippage’ of a perfect microsatellite evolution following the step-wise mutational model. The patterns of heteroplasmy were found to be shifted between generations and among siblings but rather stable between blood and feather samples. This study provides the first evidence of a very extensive mtDNA length polymorphism and heteroplasmy in the highly inbred Crested Ibis which carries an mtDNA genome lack of structural genetic diversity. The analysis of pedigreed samples also sheds light on the transmission of mtDNA length heteroplasmy in birds following the genetic bottleneck theory. Further research focusing on the generation and transmission of particular mtDNA heteroplasmy patterns in single germ line of Crested Ibis is encouraged by this study.

Macroscopic Fundamental Diagram for Urban Streets and Mixed Traffic

In the past decade many papers focused on describing the vehicular traffic stream of an arterial on an aggregate level. Unfortunately, in this considerable body of research, only a few papers account for bus systems. This paper tries to fill that gap by investigating two potential methods for estimating macroscopic fundamental diagrams of multimodal transport systems of a signalized arterial. The first approach models the motion of buses endogenously by extending the existing estimation method with the moving bottleneck theory; the second approach proposes to incorporate the effects of buses exogenously. The estimated macroscopic fundamental diagrams were then cross compared with results provided by microsimulation software that finely reproduced the traffic stream. Mean speeds of vehicles and buses produced by the different methods were similar and consistent. Finally, results of the three methods were expressed for levels of service and compared with the levels of service of the Highway Capacity Manual 2010.

Compact and adaptive spatial pyramids for scene recognition

Most successful approaches on scene recognition tend to efficiently combine global image features with spatial local appearance and shape cues. On the other hand, less attention has been devoted for studying spatial texture features within scenes. Our method is based on the insight that scenes can be seen as a composition of micro-texture patterns. This paper analyzes the role of texture along with its spatial layout for scene recognition. However, one main drawback of the resulting spatial representation is its huge dimensionality. Hence, we propose a technique that addresses this problem by presenting a compact Spatial Pyramid (SP) representation. The basis of our compact representation, namely, Compact Adaptive Spatial Pyramid (CASP) consists of a two-stages compression strategy. This strategy is based on the Agglomerative Information Bottleneck (AIB) theory for (i) compressing the least informative SP features, and, (ii) automatically learning the most appropriate shape for each category. Our method exceeds the state-of-the-art results on several challenging scene recognition data sets.

Resequencing Data Provide No Evidence for a Human Bottleneck in Africa during the Penultimate Glacial Period

Based on the accumulation of genetic, climatic, and fossil evidence, a central theory in paleoanthropology stipulates that a demographic bottleneck coincided with the origin of our species Homo Sapiens. This theory proposes that anatomically modern humans--which were only present in Africa at the time--experienced a drastic bottleneck during the penultimate glacial age (130-190 kya) when a cold and dry climate prevailed. Two scenarios have been proposed to describe the bottleneck, which involve either a fragmentation of the range occupied by humans or the survival of one small group of humans. Here, we analyze DNA sequence data from 61 nuclear loci sequenced in three African populations using Approximate Bayesian Computation and numerical simulations. In contrast to the bottleneck theory, we show that a simple model without any bottleneck during the penultimate ice age has the greatest statistical support compared with bottleneck models. Although the proposed bottleneck is ancient, occurring at least 130 kya, we can discard the possibility that it did not leave detectable footprints in the DNA sequence data except if the bottleneck involves a less than a 3-fold reduction in population size. Finally, we confirm that a simple model without a bottleneck is able to reproduce the main features of the observed patterns of genetic variation. We conclude that models of Pleistocene refugium for modern human origins now require substantial revision.